In recent years, hold-type display devices provided with a liquid crystal module or an EL display module are increasingly used in the fields where CRTs (Cathode Ray Tubes) have been used.
However, it is said that the quality of video in such a hold-type display device falls behind that of an impulse-type display device such as CRTs (Cathode Ray Tubes) in which a light-up period during which an image is displayed and a light-off period during which an image is displayed are repeatedly alternated.
In other words, in a typical hold-type display device, the entire one frame period is the light-up period. As such, when a frame image is refreshed, the displayed object stays in the same position and is displayed until the image is refreshed to the next frame image. In the eyes of the viewers, this looks as a blurry motion.
Aiming at improvement of video quality as one of objects, various subframe-displaying methods of in which a frame for displaying a single image is divided into plural subframes have been suggested. For example, patent citations 1 to 4 discloses such methods.
Further, in an image display device adopting an organic LED panel, multiplexing of vertical scanning have been conventionally conducted.    [Patent Citation 1]    Japanese Unexamined Patent Publication No. 302289/1994 (Tokukaihei 4-302289; Published on Oct. 26, 1994)    [Patent Citation 2]    Japanese Unexamined Patent Publication No. 281625/2001 (Tokukai 2001-281625; Published on Oct. 10, 2001)    [Patent Citation 3]    Japanese Unexamined Patent Publication No. 23707/2002 (Tokukai 2002-23707; Published on Jan. 25, 2002)    [Patent Citation 4]    Japanese Unexamined Patent Publication No. 22061/2003 (Tokukai 2003-22061; Published on Jan. 24, 2003)    [Patent Citation 5]    Japanese Unexamined Patent Publication No. 297094/2002 (Tokukai 2002-297094; Published on Oct. 9, 2002)